Your working memory capacity, or the amount of information you're able to actively hold in your mind at once, isn't just easy-access storage in your brain. According to Art Markman (Ph. D), writing for Psychology Today, a better working memory increases your capacity to generate creative idea. One study demonstrates:

In one study, the researchers actually explored the creativity of improvisations played by cellists with no formal training in improvisation. At the start of the study, they measured everyone's working memory capacity. Then, participants were given the chance to perform three 3-minute improvisations based on a theme (such as Winter or Spring). Each improvisation had a different theme. The improvisations were recorded in a studio, and then professional musicians rated them for their originality and creativity. The creativity of the first improvisations people performed was about the same regardless of their working memory capacity. However, the people with high working memory capacity played better improvisations as they progressed through the study, while those with low working memory capacity played worse improvisations. So, by the end of the study, the people with higher working memory capacity were playing significantly more creative improvisations than those with low working memory capacity.

According to this study, and others mentioned by Markman, working memory looks to have an effect on the types of ideas you generate. When we try to come up with new ideas, we almost always start with the familiar. People with low working memory capacities just stick with that familiar stuff. People with high working memory capacities, however, start to depart from the usual and begin to look outside of what they already know.

So how do you increase your working memory capacity? While there are no definitive methods, there are several things believed to be helpful. Improving reading comprehension is one, which can be done by reading more often and paying close attention to what you read. With every sentence, you should be able to recall it in memory afterwards—even if that recollection is only temporary. Practicing this can make a difference. Additionally, dual n-back training can actually help your brain focus better on tasks and this should help your working memory. Brain Workshop is one free game that can get you started. In addition to focusing better, breaking down information you want to remember into small chunks can help. Simple information is almost always going to be easier to remember.

While research is still ongoing and there are no definitive answers, your working memory capacity is shaping up to be an important factor in how you think all-around. Spend some time with it and you may find it easier to generate better ideas.